What kind of work will a boy, weighing 50 kg, do, climbing the rope to a height of 3 m?

if the boy rose from a height of 0 m, then A = Ep = mgh (work is the difference in energy, and since the term turns to 0, then the energy is equal to work)
A = 50 * 3 * 10 = 1500 (J) or 1.5 (KJ)

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